Diagnosis

During the physical exam, your doctor may check for:

• Signs of muscle weakness in your arms, legs, hands and feet
• Decreased muscle bulk in your lower legs, resulting in an inverted champagne bottle appearance
• Reduced reflexes
• Sensory loss in your feet and hands
• Foot deformities, such as high arches or hammertoes
• Other orthopedic problems, such as mild scoliosis or hip dysplasia

Your doctor may also recommend the following tests, which can help provide information about the extent of your nerve damage and what may be causing it.

• Nerve conduction studies. These tests measure the strength and speed of electrical signals transmitted through your nerves. Electrodes on the skin deliver small electric shocks to stimulate the nerve. Delayed or weak responses may indicate a nerve disorder such as Charcot-Marie-Tooth disease.
• Electromyography (EMG). A thin needle electrode is inserted through your skin into the muscle. Electrical activity is measured as you relax and as you gently tighten the muscle. Your doctor may be able to determine the distribution of the disease by testing different muscles.
• Nerve biopsy. A small piece of peripheral nerve is taken from your calf through an incision in your skin. Laboratory analysis of the nerve distinguishes Charcot-Marie-Tooth disease from other nerve disorders.
• Genetic testing. These tests, which can detect the most common genetic defects known to cause Charcot-Marie-Tooth disease, are done with a blood sample. Genetic testing may give people with the disorder more information for family planning. It can also rule out other neuropathies. Recent advances in genetic testing have made it more affordable and comprehensive. Your doctor may refer you to a genetic councilor before testing so you can best understand the pros and cons of testing.